LIEBHERR S 800 Gear Hobbing Machine
General Information
- Manufacturer: Liebherr – Lorenz
- Model: S 800
- Condition: Good (used)
Machine Condition & Accessories
- Well-maintained machine with comprehensive accessories
- 1 × pallet of change gears
- 1 × pallet of hobbing cutters
- 1 × pallet of arbors
- Complete documentation included
Technical Specifications
- Max. workpiece length with counter support: 600 mm
- Max. workpiece length with counter support retracted: 800 mm
- Max. travel of milling slide: 360 mm
- Largest pitch machinable with largest workpiece: 5 Pi
- Largest pitch machinable (standard range): 8 Pi
- Milling spindle taper: MT 5
- Arbor diameters: 22 / 27 / 32 / 40 mm
- Max. cutter diameter: 186 mm
- Max. cutter length: 170 mm
- Max. cutter shift: 80 mm
- Cutter speed range: 40 – 220 rpm
- Feed rates steplessly adjustable:
- Horizontal
- Vertical
- Tangential
- Clamping table diameter (without coolant rim): 550 mm
- Clamping table bore: 100 mm
- Clamping arbor taper: MT 5
Machine Dimensions & Weight
- Overall dimensions (L × W × H): 3.6 × 1.8 × 1.9 meters
- Machine weight: 5,000 kg
Technical Evaluation of the Liebherr–Lorenz S 800
Gear Hobbing Machine (Used)
1. Technical Evaluation Overview
The Liebherr-Lorenz S 800 is a conventional gear hobbing machine designed for the production of cylindrical gears within defined size and pitch limits. The machine is described as well maintained and supplied with comprehensive accessories, including pallets of change gears, hobbing cutters, arbors, and documentation, which is relevant for operational flexibility and setup continuity.
Workpiece capacity is specified with a maximum length of 600 mm using counter support, extendable to 800 mm with the counter support retracted. The milling slide travel of 360 mm defines axial cutting movement limits. Pitch capability is stated as up to 5 Pi with the largest workpiece, and up to 8 Pi in the standard range, indicating suitability for coarse to medium pitch gears within these bounds.
The milling spindle uses an MT5 taper, supporting arbors of 22, 27, 32, and 40 mm. Maximum cutter dimensions are 186 mm diameter and 170 mm length, with a maximum cutter shift of 80 mm. Cutter speeds are specified from 40 to 220 rpm, and feed rates are steplessly adjustable in horizontal, vertical, and tangential directions.
The clamping table diameter of 550 mm, with a 100 mm bore and MT5 clamping arbor taper, defines workholding constraints. Overall machine dimensions are 3.6 × 1.8 × 1.9 meters, with an approximate weight of 5,000 kg.
2. What to Check Before Buying
Mechanical inspection should focus on the hob spindle bearings, arbor seating surfaces, and slideways, as these directly affect gear accuracy and surface quality. Wear in the change gear train should be assessed, especially since pitch generation depends on mechanical gearing rather than CNC interpolation.
The feed mechanisms—horizontal, vertical, and tangential—should be tested across their full adjustment range to confirm smooth, backlash-free motion. The counter support should be checked for alignment and rigidity when engaged, as it influences stability on longer workpieces.
Accessory condition is critical: hobbing cutters should be inspected for wear or damage, arbors for runout, and change gears for tooth condition. Documentation completeness should be verified against the actual configuration of the machine.
3. Typical Industrial Applications
Based on the provided specifications, this machine is suited for external gear hobbing of medium-sized cylindrical gears within the stated pitch and length limits. Typical applications include industrial gearbox components, power transmission gears, and general mechanical drive elements, where conventional hobbing processes are appropriate and CNC-level flexibility is not required.
4. Common Risks in Used Machines
Common risks for used gear hobbing machines include mechanical wear in spindle bearings, slides, and change gear sets, which can affect pitch accuracy and tooth form. Misalignment of the counter support or wear in feed mechanisms can lead to taper or profile errors. As a mechanically driven system, performance is also sensitive to missing, damaged, or mismatched change gears.
5. Maintenance and Service Considerations
Maintenance requirements depend on historical usage and service practices, which are not detailed. Regular attention should be given to lubrication of slides and gearing, spindle bearing condition, and cleanliness of mechanical interfaces. Long-term serviceability benefits from the included documentation and accessory sets, but availability of replacement mechanical components should be confirmed.
Given the machine’s mass and footprint, any major service or realignment work should be planned with appropriate handling and foundation considerations.
Final Note:
While capacities, tooling limits, and accessories are clearly stated, information such as achievable gear accuracy class, service history, and spindle condition is important. These factors should be verified through inspection, trial cutting, and documentation review before forming final technical conclusions.
